@article{HackHanischSchenkel2016,
  author    = {Hack, Thomas-Paul and Hanisch, Florian and Schenkel, Alexander},
  title     = {Supergeometry in Locally Covariant Quantum Field Theory},
  series = {Communications in mathematical physics},
  volume    = {342},
  journal   = {Communications in mathematical physics},
  publisher = {Springer},
  address   = {New York},
  issn      = {0010-3616},
  doi       = {10.1007/s00220-015-2516-4},
  pages     = {615 -- 673},
  year      = {2016},
  abstract  = {In this paper we analyze supergeometric locally covariant quantum field theories. We develop suitable categories SLoc of super-Cartan supermanifolds, which generalize Lorentz manifolds in ordinary quantum field theory, and show that, starting from a few representation theoretic and geometric data, one can construct a functor U : SLoc -> S*Alg to the category of super-*-algebras, which can be interpreted as a non-interacting super-quantum field theory. This construction turns out to disregard supersymmetry transformations as the morphism sets in the above categories are too small. We then solve this problem by using techniques from enriched category theory, which allows us to replace the morphism sets by suitable morphism supersets that contain supersymmetry transformations as their higher superpoints. We construct superquantum field theories in terms of enriched functors eU : eSLoc -> eS*Alg between the enriched categories and show that supersymmetry transformations are appropriately described within the enriched framework. As examples we analyze the superparticle in 1 vertical bar 1-dimensions and the free Wess-Zumino model in 3 vertical bar 2-dimensions.},
  language  = {en}
}
@article{BeniniSchenkel2017,
  author    = {Benini, Marco and Schenkel, Alexander},
  title     = {Quantum Field Theories on Categories Fibered in Groupoids},
  series = {Communications in mathematical physics},
  volume    = {356},
  journal   = {Communications in mathematical physics},
  publisher = {Springer},
  address   = {New York},
  issn      = {0010-3616},
  doi       = {10.1007/s00220-017-2986-7},
  pages     = {19 -- 64},
  year      = {2017},
  abstract  = {We introduce an abstract concept of quantum field theory on categories fibered in groupoids over the category of spacetimes. This provides us with a general and flexible framework to study quantum field theories defined on spacetimes with extra geometric structures such as bundles, connections and spin structures. Using right Kan extensions, we can assign to any such theory an ordinary quantum field theory defined on the category of spacetimes and we shall clarify under which conditions it satisfies the axioms of locally covariant quantum field theory. The same constructions can be performed in a homotopy theoretic framework by using homotopy right Kan extensions, which allows us to obtain first toy-models of homotopical quantum field theories resembling some aspects of gauge theories.},
  language  = {en}
}
@article{BeniniSchenkel2017,
  author    = {Benini, Marco and Schenkel, Alexander},
  title     = {Poisson Algebras for Non-Linear Field Theories in the Cahiers Topos},
  series = {Annales de l'Institut Henri Poincar{\´e}},
  volume    = {18},
  journal   = {Annales de l'Institut Henri Poincar{\´e}},
  publisher = {Springer},
  address   = {Basel},
  issn      = {1424-0637},
  doi       = {10.1007/s00023-016-0533-2},
  pages     = {1435 -- 1464},
  year      = {2017},
  language  = {en}
}
@misc{BeckerSchenkelSzabo2017,
  author    = {Becker, Christian and Schenkel, Alexander and Szabo, Richard J.},
  title     = {Differential cohomology and locally covariant quantum field theory},
  series = {Reviews in Mathematical Physics},
  volume    = {29},
  journal   = {Reviews in Mathematical Physics},
  number    = {1},
  publisher = {World Scientific},
  address   = {Singapore},
  issn      = {0129-055X},
  doi       = {10.1142/S0129055X17500039},
  pages     = {42},
  year      = {2017},
  abstract  = {We study differential cohomology on categories of globally hyperbolic Lorentzian manifolds. The Lorentzian metric allows us to define a natural transformation whose kernel generalizes Maxwell's equations and fits into a restriction of the fundamental exact sequences of differential cohomology. We consider smooth Pontryagin duals of differential cohomology groups, which are subgroups of the character groups. We prove that these groups fit into smooth duals of the fundamental exact sequences of differential cohomology and equip them with a natural presymplectic structure derived from a generalized Maxwell Lagrangian. The resulting presymplectic Abelian groups are quantized using the CCR-functor, which yields a covariant functor from our categories of globally hyperbolic Lorentzian manifolds to the category of C∗-algebras. We prove that this functor satisfies the causality and time-slice axioms of locally covariant quantum field theory, but that it violates the locality axiom. We show that this violation is precisely due to the fact that our functor has topological subfunctors describing the Pontryagin duals of certain singular cohomology groups. As a byproduct, we develop a Fr{\´e}chet-Lie group structure on differential cohomology groups.},
  language  = {en}
}
@article{BeckerBeniniSchenkeletal.2019,
  author    = {Becker, Christian and Benini, Marco and Schenkel, Alexander and Szabo, Richard J.},
  title     = {Cheeger-Simons differential characters with compact support and Pontryagin duality},
  series = {Communications in analysis and geometry},
  volume    = {27},
  journal   = {Communications in analysis and geometry},
  number    = {7},
  publisher = {International Press of Boston},
  address   = {Somerville},
  issn      = {1019-8385},
  doi       = {10.4310/CAG.2019.v27.n7.a2},
  pages     = {1473 -- 1522},
  year      = {2019},
  abstract  = {By adapting the Cheeger-Simons approach to differential cohomology, we establish a notion of differential cohomology with compact support. We show that it is functorial with respect to open embeddings and that it fits into a natural diagram of exact sequences which compare it to compactly supported singular cohomology and differential forms with compact support, in full analogy to ordinary differential cohomology. We prove an excision theorem for differential cohomology using a suitable relative version. Furthermore, we use our model to give an independent proof of Pontryagin duality for differential cohomology recovering a result of [Harvey, Lawson, Zweck - Amer. J. Math. 125 (2003), 791]: On any oriented manifold, ordinary differential cohomology is isomorphic to the smooth Pontryagin dual of compactly supported differential cohomology. For manifolds of finite-type, a similar result is obtained interchanging ordinary with compactly supported differential cohomology.},
  language  = {en}
}